A high-end instrumentation grant is requested to purchase a research- dedicated 3.0 T Siemens Verio MRI scanner for human translational and clinical imaging research at St. Jude Children's Research Hospital. St. Jude is a charitably funded institution dedicated to advancing cures for catastrophic diseases of childhood through treatment and research. Imaging scientists and clinical investigators will use the instrument in major NIH-funded research programs to study children with pediatric cancers, sickle cell disease, and HIV/AIDS, and also adult survivors of these diseases. The objectives of the research to be conducted with the MRI scanner are to understand disease pathogenesis, improve diagnosis and assessment of disease extent, enhance treatment outcome, and quantitate adverse consequences of treatment. Currently, MRI imaging research activities of St. Jude investigators are accommodated by 3 clinical MRI scanners (two 1.5 T, one 3.0 T), but current resources are no longer sufficient because of rapid growth in demand for both clinical and research MR imaging. Research studies account for approximately 50% of all scans on the existing scanners, which operate at greater than 90% of capacity. The high utilization rate of available MRI scanners limits the efficiency of current research projects because of difficulty scheduling examinations, discourages colleagues in clinical investigation from collaborative imaging research objectives, and precludes the initiation of important new lines of investigation because imaging time is always sparse and sometimes unavailable. The 3T instrument is urgently needed to support the human imaging needs of NIH- supported biomedical researchers at St. Jude. The Verio scanner was chosen because it includes the most advanced MRI technology available, and because the St. Jude imaging scientists, in-house service engineers, and MRI Technologists who will operate the system have expertise in Siemens system software and hardware architecture. The scanner will be located in an existing empty MRI bay adjacent to our clinical MRI scanners. With institutional commitments to complete the vacant bay (RF and magnetic shielding, completion of internal features) and support initial operational costs, the new system will be installed and operational within 6 months of the grant award. The installation of this MRI scanner will lead to the creation of 2 jobs at St. Jude within the first 6 months of the award for direct operational support of the system, and we anticipate an additional 2 positions for post doctoral fellows, graduate students, and research assistants within 24 months to support the expanded research programs of participating investigators. Access to the research-dedicated scanner will also help ensure the jobs of the employees currently supported by NIH users'grants;purchase of the Verio system will help to sustain and grow the Siemens workforce in the United States. American Recovery and Reinvestment Act funds invested in this instrument will be put to work quickly for compelling research programs to improve the health of children, our most important national resource. PUBLIC HEALTH RELEVANCE: A state-of-the-art MRI scanner is needed for research at St. Jude Children's Research Hospital to improve the lives of children with cancer, sickle cell disease, and HIV/AIDS, and also adult survivors of these diseases. The objectives of the research are to understand the causes of disease, improve diagnosis and assessment of disease extent, and quantify side effects of treatment - all leading toward increased survival and improved quality of life for survivors. Purchase of the MRI scanner, a Siemens Verio that is designed and manufactured to reduce adverse environmental impact, will create 4 jobs at St. Jude Children's Research Hospital within 2 years, support construction activities at St. Jude, and strengthen the employment position of Siemens Medical Solutions in the United States.